Diet and other early exposures may affect child development and the risk of several chronic diseases, but additional research is needed. [unreadable] [unreadable] The current research described in this catch-all project comprises five subprojects: first, a study of effects due to exposures incurred secondary to dental procedures and treatments during pregnancy; second, a study having to do with hormone levels in women during pregnancy in relation to factors in offspring, which are risk factors for testicular germ cell tumors; third, a study of maternal body mass index in relation to time it took to become pregnant; fourth, a study of risk factors for nonalcoholic fatty liver disease among adolescents, and finally, a didactic paper describing a new statistical method to epidemiologists.[unreadable] [unreadable] The study of effects due to exposures incurred secondary to dental procedures and treatments during pregnancy is based on data from the Avon Longitudinal Study of Parents and Children. Data on dental history were available for 8,251 women and the outcomes examined were birth weight, preterm birth, and childs communicative development. Dental care during pregnancy was not related to preterm birth, birth weight, or neurodevelopment. X-rays for dental care during pregnancy, however, were associated with an increased risk of low birth weight newborns.[unreadable] [unreadable] Regarding the study of hormone levels during pregnancy, this was nested in the Collaborative Perinatal Project (CPP--see description under project ES049016). Stored serum from pregnant women was analyzed for hormone levels and examined in relation to subject characteristics. The results show that the relation of maternal hormone levels to characteristics such as height, obesity, age are different for blacks and whites, which is an important consideration when studying risk factors for testicular germ cell cancer in offspring.[unreadable] [unreadable] The study of body mass index (obesity) and time to pregnancy also was based on data from the Collaborative Perinatal Project. This study showed that obese women take longer to get pregnant.[unreadable] [unreadable] The study of nonalcoholic fatty liver disease among adolescents took advantange of newly available data from the National Health and Nutrition Examination Survey, 1999-2004. The prevalence of this potentially serious condition was found to be suprizingly high--8%.[unreadable] [unreadable] The didactic piece on methods employed data examples from several studies. The methods described are useful for nested studies of continuous outcomes. [unreadable] [unreadable] Last years progress:[unreadable] Four papers were published (see list below), and one was accepted for publication.